The invention relates to a method for remote-control programming of machine control systems, and to a PC-based machine control system for performing the method.
An automated production system usually has many machines, each with corresponding machine control systems in which a compiled control program is stored in memory. Upon startup and when changes are made, such as in optimizing production sequences, searching for errors and error correction, and so forth, individual control programs or all the control programs, such as SPS control programs, must often be generated or modified.
Although the capability of executing a control program source is present in each machine control system, the execution is usually performed by a separate programming device provided specifically for that purpose. It can for instance be a PC, and in particular a notebook. This has the advantage that the execution/setup of the control program source can be done centrally on only a single programming device. This can also be done at a completely different place from where the applicable machine or machine control system is located. Another advantage is that both operation of the machine via the operation and visualization module of the machine control system and execution of the control program—in particular, a status display of control signals in debugging the control program—can be done simultaneously with the programming device. To that end, it is known to establish a connection between the programming device and the applicable machine control system, via a serial direct interface between these devices. This is followed by an upload of the control program source from the machine control system into the programming device. The execution is then done via a programming module in the programming device. Next, the executed/set-up control program source is compiled, and the compilate is downloaded into the machine control system. Next, the machine control system is provided with the executed compilate, and the user can disconnect the programming device from the machine control system. At the same time, as a rule there is also a programming module in each machine control system, which always includes the applicable compiler. It is therefore possible to execute the control program, compile it, and load it into a control module of the machine control system directly at the machine control system. Usually, this is the case if the adaptation/modification is relatively slight.
A download of both the control program source and the compilate into the machine control system must always be done. If the download of the control program source into the machine control system is not done, the result is inconsistency of the compilate stored in memory there and the control program source. If a (post-) execution takes place in the in the machine control system, and the newly generated control program source is compiled and downloaded into a control module of the machine control system, then the previously executed compilate may be lost under some circumstances. In the prior art, this is always possible. That is, it is quite possible that (for instance unintentionally), the download of the control program source into the machine control system fails to take place, resulting in the aforementioned inconsistency. In that case, the compilate is newer than the control program source.